Telephone-transmitter



(No Model.)

J. E. FULLER. T TELEPHONE TRANSMITTER.

No. 316,888. Patented Apr. 28, 1885 INVENTOR WITNESSES mm STATES PATENT, O FICE.

J. ENSIGN FULLER, or CHICAGO, ILLINOIS.

TELEPHONE-TRANSMITTER.

SPECIFICATION forming part of Letters Patent No. 316,888,- dat d April 28, 1885.

Application filed January 7, 1884.

To all whom it may concern:

Be itknown that I, J. ENSIGN FULLER, acitizen of the United States, residing at Chicago, in the county of Cookand State of Illinois, have invented certain new and useful Improvementsin Telephone-Transmitters, of which the following is aspecification, reference being had therein to the accompanying drawings.

Figure l is a view in perspective of my invention as adjusted upon the inside door of the transmitter. Fig. 2 is a vertical sectional view thereof through linear x of Fig. 3. Fig. 3 is a plan view of the instrument. Figs. 4, 5, and 6 represent modifications of the devices for regulating the position of the electrodes, Fig. 4 showing two adjusting-nuts, one above the bar 0 and the other below,to act as a locknut, Fig. 5 showing the threaded screw passing through the metal bar 0, with no insulating-ring around said screw, but showing the insulated end to lever F, and Fig 6 showing the nut m passingthrough the insulating'ring.

A is the door of the transmitter; a, the orifice through which the sound-waves reach the diaphragm.

B is the diaphragm.

b is a soft-rubber ring surrounding the periphery of the diaphragm.

b b are springs which hold the diaphragm in position.

D is a metallic base which supports lugs ll.

e is the wire leading from hinge Kto base D.

e is the wire leading from post h to hinge K.

The transmitter is connected with one pole of the battery by wire 0 to hinge K, the circuit being from hinge K to base D, thence through trunnion t, lever F, and platinum point p to the carbon button d, from said button over bar 0 to post IL, thence by wire 6 to hinge K, and to the battery.

From post his suspended a solid metallic bar, C, by a stiff spring, 0, and screws 8 s.

g is a metallic cup fastened to the bar 0 by a screw, it, and holds the carbon button d.

F is an automatic reacting lever composed of metal pivoted at t, and supported at either end by screwsff, which pass through lugs ll,

p is a wire held by lever F, and in constant contact but not integral with the diaphragm. p is a platinum point, also held firmly by lever F, and in constant contact with carbon (N0 model.)

button (1. m is a threaded pin, to which are attached spring 1' and hookr, around which is placed the adjusting-nut m. which adjusts the bar 0 and the leverF, thus regulating the juxtaposition of the two electrodes.

m is a ring set in, the bar 0, composed of gelatinized fiber or any good insulating ma terial, and through which passes pin m, thus preventing a short circuit from lever]? to barC. 6 0

The object of my invention is to furnish means by which the. limit of variation in, the strength of an electriccurrent is increased or made greater than heretofore, j

The invention is applied to an .electriccun 6 5 rent, which, upon beingmude'vibratory or undulatory by the variation of impact between the electrodes, is used for the transmission orv reproduction telephonically of speech, signals, and all kinds of sounds that can be made to produce vibratory motionin diaphragms. The invention is intended to render such transmission or reproduction more perfect and clear than heretofore and my invention only refers to the use of an electric current thus made vibratory or undulatory, as contra-distinguished from an intermittent or broken current.

I do not restrict myself to the exact mechanical arrangement shown to which I limit my description, because the samemay be modified in various ways without imparting new qualities or producing different results. For instance, the entire bar 0 might be constructed in more than one piece, or it might be made in one piece more susceptible to vibration, which should be very thin at its junction with post h, and gradually thickened toward the point where thumb-screw m passes through it. Other changes of form, size, or arrangement might be made which would he obviously mere 0 modifications of the apparatus described.

In the commercial adaptation for several years of the transmitters now in use it has many times been my unpleasant experience to find that when speaking too loudly in order 5 to overcome some cross or fault in thecline, or because the battery-power was weak, or where from other causes the ordinary tones of the voice were nearly unintelligible to the listener, the electrodes were thrown entirely apart, thus 10o preventing any vocal sound whatever from being transmitted. To produce a telephone that would absolutely overcome this serious fault has been my effort, and my invention is the result of a long range of careful experiments for this purpose, in that, instead of any tendency to throw the electrodes apart by loud speaking, the action of my reacting lever or levers necessarily causes them to receive a closer pressure by the increased amplitude of the vibrations of the diaphragm, and thus transmit the exact modulations of the soundwaves thrown thereon.

The operation of the apparatus shown herev in is as follows Upon speakin g into the mouthpiece there is given to the diaphragm a forward-- and-back movement, which is increased at the point of contact-via, the platinum point and the carbon buttonby means of the lever F and the bar 0, which, being united by wire 1" and post m, constantly and automatically vary the pressure at such point of contact. These rapid movements forward and back cause vibrations in the current, but do not and cannot break it, for the reason that the platinum point and the carbon button are always in contact more orless close, according to the force of the sound- Waves. Thus, as the lever F, being pivoted on trunnions t, is propelled forward at one end by the action of a sound-wave, it is necessarily and simultaneously repelled to an equal degree at its opposite end, and because this opposite end is joined to bar 0 by wire r, pin m, an equal and simultaneous depression is caused in bar 0 throughout its entire length,

and with it the carbon button is brought toward the platinum point and in close contact with it.

I am aware that reacting arms or levers carrying electrodes have been used, and I do not claim such arms or levers, broadly.

Having thus described my invention, what I claim, and desire to secure by Letters Patent,

1. The combination, with the diaphragm, of the approximately equal-armed lever F, having one end impinging on the diaphragm and supporting electrode p, the lever O, carrying electrode (1, and the adjustable connection be tween an intermediate portion of said lever O and the end of lever F opposite that which carries its electrode, substantially as described.

2. The lever O, pivoted at one end and carrying electrode 01 at the other end, the lever F, pivoted at about its middle and supporting atone end electrode 1;, and the link connecting the other end of said lever with an intermediate portion of lever O, in combination with the diaphragm and intermediate mechanism operated thereby for impartingits direct movement to electrode 1), all as set forth.

In testimony whereof I affix my signature in presence of two witnesses.

J. ENSIGN FULLER.

Witnesses:

L. W. SEELY, E. M. MARBLE. 

